Radioactive waste material incinerator



NOV- 23 1965 c. F. BERGHOUT ETAL 3,218,997

RADIOACTIVE WASTE MATERIAL INCINERATOR 4 Sheets-Sheet 1 Filed Feb. 6,1963 INVENTQQS CHmSTIAN E esuouv MAxwau. BAUER FRANcM/.LAMARV QAMQN P.Mmx

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` NOV- 23, 1955 c. F. BERGHOUT ETAL 3,218,997

RADIOACTIVE WASTE MATRIAL INGINERATOR Filed Feb. 6, 1963 4 Sheets-Sheet2 RESSURE GAGES lNvEN-rQvZ/S Cueva-HAN F. BERGHOQT MAXWELL DAW-:K2

FrzANcvs VV. LANAQO RAMON P. MxNX WALTEQ E. 'SENOSKI UQAL T WARDATTQQNEY Nov. 23, 1965 c. F. BERGHOUT ETAL 3,218,997

RADIOACTIVE WASTE MATERIAL INCINERATOR Filed Feb. 6, 1963 4 Sheets-Sheet5 MAxWELL DAuElz FQANOS W LAM/m2o RAMON I? Mmx WAL-V52 E. suosKlUQALT-WA2D ATTORNEY NOV- 23, 1965 c. F. BERGHOUT ETAL 3,218,997

RADIOACTIVE WASTE MATERIAL INCINERATOR Filed Feb. 6, 1963 4 Sheets-Sheet4 Fica? NvENTolze Curas-HAN FBERGHOUT- MAxwELL DAUEQ FQANQeW. LANARDQAMON P. Mmmv WALTEQ ESENDSKI U AL- T. WARD @MMV ATTQQNEY United StatesPatent O 3 21s 997 RADroACTIvE WAST MTERIAL INCINERATOR Christian F.Berghout, Lutherville, Md., Maxwell Dauer,

Miami, Fla., Francis W. Lanard, Silver Spring, Md.,

The invention described herein may be manufactured and used by or forthe Government for governmental purposes without the payment to us ofany royalty thereon.

The present invention relates to incinerators and more particularly toincinerators for the disposal of combustible radioactive waste material.i The increasing use of radioactive material throughout the worldpresents an increasingly critical problem of disposal of radioactivecontaminated materials. Such of these radioactive materials as arecombustible, may be much more easily disposed of if they can besubjected to incineration and the consequent reduction in volume. Thisincineration can be accomplished if the release of hazardous amounts ofradionuclides into the environment can be prevented.

Accordingly, it is an object of this invention to provide an incineratorfor combustible radioactive waste material which is so designed as toprevent the release of hazardous amounts of radionuclides into theenvironment while at the same time providing easy collection means ofthe radioactive ash for disposal thereof.

Another obje-ct of this invention is to provide a radioactive wastematerial incinerator which may be operated with the least possibleexposure of the operating personnel to radionuclides.

Other objects and advantages will be apparent to those skilled in theart upon reference to the following descriptions and the accompanyingdrawings in which:

FIG. 1 is an elevational view of the preferred embodiment;

FIG. 2 is a plan view of the preferred embodiment;

FIG. 3 is a view taken on t-he line 3-3 of FIG. 2;

FIG. 4 is a veiw taken on the line 4-4 of FIG. 1;

FIG. 5 is a view taken on the line 5-5 of FIG. 1;

FIG. 6 is a view taken on the line 6-6 of FIG. 4;

FIG. 7 is 'a view taken on the line 7--7 of FIG. l;

FIG. 8 is a view taken on the line 8--8 of FIG. l;

FIG. 9 is a view taken on the line 9-9 of FIG. 1; and

FIG. 10 is a detailed view of a charging door as used =in thisembodiment. j

Brieily the incinerator comprises a closed system silotype combustionchamber for the mass burning of combustible radioactive material, havinga refractory, iron shaking grates, and two fuel injection burners; acharging chute; a concrete hood; a discharge chute surrounded by a steelwater jacket; a dynamic precpitator with discharge hopper; a filtercontainer; and a stack.

Referring in detail to the preferred embodiment of this invention asdepicted in the accompanying gures, combustion chamber 1 has an exteriorconstruction of common brick and an interior construction of iire brick.It is equipped with a refractory 7, two sections of shaking grates 4,and two fuel injection burners 2. The fuel injection burners are air togas type and are protected by bent rods 3. Grates 4 rest on a 30"-poundrail 9 which .is mounted in the refractory 7 to prevent the warping ofcastings. At the top of the combustion chamber is a rod screen 5 of amesh of approximately 11/2 inches with rods of l/g inch in diameter, thefunction of which is to prevent heavy lfrarne of the chamber.

particles of y `ash from entering the system. Below the grate 1s airinlet 6 through which, by means of a 6 inch dlarneter pipe, additionalmake up air for burning may be introduced. Inlet 6 has a completeshutoff back pressure valve for safety. Air inlet 6 is supplement-ary tothe principal air make up system which introduces, through air vents 8,the primary air supply for the combustion. In this embodiment, four 3inc-h air vents 8 are prov1ded, each vent being equipped with a shutoffvalve 1.0 to be used in the event of pressure blow back. In additron, aregulating butterfly valve 11 is provided to control the air flow and toprovide a complete shutoff until the individual vents have been closed.The air itself is provided by blower 12 which is belt driven from motor13. A1r is transmitted from blower 12 to vent 8 by means of rectangulardust 14 (shown in detail in FIG. 8.) which is provided with air controlvanes 95.

Combustible radioactive material is introduced into the combustionchamber through charging chute 15. Charging chute 15 is compartmented toreduce the hazard j of direct blow back of contaminated dust, smokeparticles, and heat. To provide this compaitmentation, the chute 'isequipped with an inner door 16 through which protrudes observation port92. The outer door 18 is hand operated by a lifting handle 19 andself-locking thu-mb latch 20 as shown in detail in FIG. 10. The door isequipped with a heavy neoprene gasket 21 to insure a tight seal. Chute15 is also provided with pusher rod 22 which is operated through anopening in door 18 having a flexible rubber gasket 23 which provides anair tight seal. In this embodiment chute 15 is connected to theincinerator combustion chamber 1 by bolts preset in the A gasket 24 isprovided to insure a seal between chute 15 and chamber 1.

Over combustion chamber 1 is concrete hood 25 which is of heat-resistantreinforced concrete.

Connected with refractory 7 under the grate of combustion chamber 1 isdischarge chute 26, which, in this embodiment, is a one foot six inchdiameter pipe having a rotating plate goggle valve 27 with handle 28 toprovide quick Iand easily controllable dumping of the ash refuse. Belowgoggle valve 27 is dust hood 29 into which is incorporated circularspray nozzle 30 (see FIG. 9) having a plurality of $46 inch diameterholes directed to converge at a spray angle below the nozzle. This spraynozzle, controlled by valve 31 is for the purpose of spraying the ashrefuse as it is dumped into drum 32 for disposal. -In the course ofdumping approximately 55 gallons of radioactive ash into the disposaldrum 32, it has been found desirable to spray approximately 5 gallons ofwater. Radioactive dust is evacuated from dust hood 29 through dust tube33 which is opened by valve 34 only when dumping is taking place.

Connected to hood 25 and surrounded by steel water jacket 35 is duct 36which forms a passage'for combustion products from combustion chamber 1into the-precipititation and filtration systems described below. Thesize of the air duct in this embodiment is one foot by 3 feet. Waterjacket 35 is provided with two 2-inch water inlets 37, each having adouble check valve at each inlet to prevent back drainage. At the top ofthe water jacket are two 3-iuch water outlets 38 allowing easy drainagefrom the uppermost portion of the water jacket. A drain plug 39, at thebase of the water jacket, provides for easy ushing and cleaning. At theend -of air duct 36 within water jacket 35 is damper 41 with handle 42for the regulation of air flow. Air duct 36 is connected to the dynamicprecipitator described below by transition assembly 43 which makes theair passage smaller, in this embodiment, from one foot by three feet toone foot by one foot and again from a rectangular to a cyclindricalpassage.

The dynamic precipitator 44 shown in this embodiment is a rotary blowertype precipitator operating at approximately 1200 r.p.m. at a rate of4,000 c.f.m. with a total pressure of inches. It is driven by 71/2horsepower motor 45.

From the dynamic precipitator the exhaust precipitate is discharged intohopper 46 through precipitator outlet 51. Hopper 46 is equipped with arotating goggle valve 48 to allow controlled discharge of theprecipitate which passes from the valve through hopper extension 47 tocollection drum 52. Dust tube 49 connects hopper extension 47 withtransition assembly 43 and accomplishes the removal of excess dustduring the dumping operation. Wedge gate valve 50 is maintained in theclosed position and opened only during the dumping operation. In thisembodiment hopper 46 is constructed of Mi inch steel and is mounted inconcrete walls.

From the dynamic precipitator the exhaust gasses pass through filterassembly 53, a desirable, but not essential feature of the incinerator,which comprises an enlargement in the exhaust conduit, containing aplurality (in this embodiment 4) of 1,000 c.f.m. ceramic type filters 91bound tightly by an asbestos belt. On one side of the assembly is door55 (shown in detail at FIG. 3). The asbestos belt described above islooped on the door side in order to allow for easy removal of thefilters. Pressure gages 54 are provided on either side yof the filterelements. Door 55 is weighted and hinge mounted. It is equipped withbars 56 which fit into sloping brackets 57 in order to bear the doortight against the filter housing. Gasket 58, a neoprene gasket, isfastened to the door and provides a seal between the door and thehousing. Guide bars (not shown) are used to guide the filter in place.Gages 54 indicate, by the amount of pressure showing thereon, whether ornot the filters are plugged.

Exhaust is conducted from the filter assembly to the stack by means ofduct 59, which in this embodiment, is constructed of 1A; inch steelplates, reinforced. The size of the duct is increased over that betweenhood 25 and assembly 43 to provide for a decrease in velocity of theexhaust. In this embodiment the duct is 24 inches square. Such adecrease in velocity is desirable in order to increase the efliciency ofthe radiation monitor alarm system in the stack.

The stack is comprised of lower section 60 and upper section 61. Section60 is of common brick, reinforced. It contains radiation detector alarmsystem 62 and recorder 63. The detector alarm system is used to indicatethe presence of excessive alpha, beta, or gamma particles being releasedinto the air. Recorder 63 maintains a constant record of the amount andintensity of radiation released into the air. Stack section 60 has inthe illustrated embodiment, an inside measurement of 2 feet 6 inches by2 feet 6 inches.

Stack section 61 is, of course, rigidly secured to the top of section 60and has transition means 69 to provide a transition from 2 feet 6 inchessquare to 2 feet diameter (cylindrical).

The incinerator is also provided with loading ramp 64 and trolley cars65 for easy handling of contaminated refuse.

Wherever it is necessary throughout the system and particularly at thedischarge hoppers, portable radiation detection and recording devices 93may be set up when a radiation check for contamination is desired.

Substitutions of equivalents within the scope of this invention arereadily foreseeable. For example an electrostatic precipitator may beused in lieu of or in addition to the dynamic precipitator or filtersystem.

We claim:

1. An incinerator for combustible radioactive material comprising:

(a) a combustion chamber having charging means for radioactive wastematerial, fuel injection means, means to support said material, and airsupply means;

(b) controlled ash disposal means at the base of and contiguous to saidcombustion chamber including an ash chute, a control valve in and forsaid ash chute, means for liquid spraying of the ash in said chute, anddust removal means for disposal of dust created by discharge of saidcombusion chamber;

(c) dynamic precipitation means for purifying waste gases emitted fromsaid combustion chamber;

(d) controlled precipitation disposal means contiguous to saidprecipitation means and including a valve controlled hopper and dustremoval means;

(e) a stack; and

(f) exhaust conduit means between said combustion chamber and saiddynamic precipitation means and between said dynamic precipitation meansand said stack.

2. The incinerator of claim 1 further including a radiation detectoralarm and recording device mounted in said stack.

3. The incinerator of claim 1 further including a radiation detectionsystem at said ash disposal means.

4. The incinerator of claim 1 further including gas filtration meansbetween said combustion chamber and said stack along said exhaustconduit means.

5. The incinerator of claim 1 wherein said exhaust conduit means betweensaid combustion chamber and said dynamic precipitation means is watercooled.

References Cited by the Examiner UNITED STATES PATENTS 881,549 3/1908Clements 110-17 1,155,492 10/1915 Krenz 110-18 2,033,685 3/1936 Contant110-10 X 2,102,427 12/ 1937 Lloyd et al. 110-8 2,767,804 10/1956 Foley55-104 2,816,621 12/1957 Weaver 55--419 2,987,459 6/ 1961 Labeyrie etal.

FREDERICK L. MATTESON, JR., Primary Examiner,

JAMES W. WESTHAVER, Examiner,

1. AN INCINERATOR FOR COMBUSTIBLE RADIOACTIVE MATERIAL COMPRISING: (A) ACOMBUSTION CHAMBER HAVING CHARGING MEANS FOR RADIOACTIVE WASTE MATERIAL,FUEL INJECTION MEANS, MEANS TO SUPPORT SAID MATERIAL, AND AIR SUPPLYMEANS: (B) CONTROLLED ASH DISPOSAL MEANS AT THE BASE OF AND CONTIGUOUSTO SAID COMBUSTION CHAMBER INCLUDING AN ASH CHUTE, A CONTROL VALUE INAND FOR SAID ASH CHUTE, MEANS FOR LIQUID SPRAYING OF THE ASH IN SAIDCHUTE, AND DUST REMOVAL MEANS FOR DISPOSAL OF DUST CREATED BY DISCHARGEOF SAID COMBUSTION CHAMBER; (C) DYNAMIC PRECIPITATION MEANS FORPURIFYING WASTE GASES EMITTED FROM SAID COMBUSTION CHAMBER: